A wooden board and boxwood pieces will outlast you if you keep two things away from them: water and extremes. Everything below follows from that.
The board
Keep it dry. Water lifts veneer and swells solid wood; a spilled glass should be wiped at once. Keep it out of direct sun and away from radiators, air conditioners and fans: heat and dry air make wood shrink, humidity makes it swell, and a board that lives next to a heater will eventually gap at the joints.
Dust it with a dry, soft cloth. Smudges and fingerprints come off with a cloth that is barely damp. If the surface feels sticky, wipe it dry. Once a month or so, a little beeswax or a furniture polish such as 3M keeps the lacquered boards looking new; our boards have a melamine lacquer that takes polish well.
The pieces
Boxwood wants the same thing as the board: no damp, no heat. Store the set in its box or pouch, not on a windowsill. Do not use polish on the pieces; a dry cloth is all they need. A piece that has taken a knock can be re-felted; write to us.
Folding and travel boards
Close them with the pieces inside their compartment, not loose on the board. Magnets do not mind temperature, but the felt does mind damp, so dry a travel set that has been in the rain before it goes back in the bag.
If something has gone wrong with a set, see the warranty or write to shop@worldchess.com.